Purple　non-sulfur　bacteria　(PNSB)　can　assimilate　ammonia,　organic　matter　and　phosphorus　in　wastewater　into　the　cell　body　to　composite　proteins　and　other　cellular　substances　under　the　condition　of　anaerobic　illumination,　instead　of　converting　to　CO2　and　N2.　In　order　to　optimize　PNSB　growth　conditions,　Rhodopseudomonas　palustris　was　used　to　study　the　effect　of　light,　nitrogen　and　carbon　on　PNSB　growth　in　this　paper.　The　results　showed　that　the　PNSB　growth　rate　under　anaerobic　infrared　illumination　conditions　is　approximately　three　times　that　of　incandescent　lamps.　PNSB　has　the　fastest　utilization　rate　of　ammonia　(NH4+-N)　and　can　utilize　nitrate　(NO3--N),　nitrite　(NO2--N).　PNSB　has　the　fastest　utilization　rate　of　sodium　acetate,　followed　by　glucose　and　starch.　This　is　because　macromolecular　organic　matter　can　only　be　further　utilized　by　PNSB　after　being　hydrolyzed　and　acidified.　It　is　a　promising　to　apply　PNSB　to　wastewater　treatment　under　anaerobic　infrared　illumination　conditions.　©　2019,　Editorial　Board　of　China　Environmental　Science.　All　right　reserved.